As it continues to crack open its platform, Yahoo has brought its Fire Eagle API out of beta, now giving users the ability to broadcast their physical location to participating sites across the Web.

Essentially, Fire Eagle is a clearinghouse that Yahoo (NASDAQ: YHOO) maintains where users can update their location, and choose which sites to share the information with.

For site owners, Fire Eagle would give them the ability to layer in a geo-aware dimension. So in that spirit, Outside.in has rolled out the feature on its community news site.

Meanwhile, Six Apart is offering a Fire Eagle connection on its Movable Type blogging platform, which it just upgraded today to mold it into more of a social network.

And for the pure-play social networks, the ability to know who's where could be especially useful for planning social events. Still, Yahoo is taking pains to brush away the Big Brother connotations that invariably spring from any type of geotracking technology.

"The user can choose how much information to share -- that's a really big deal," said Tom Coates, head of product at Yahoo Brickhouse, the division of the company that serves as a sort of in-house startup incubator. "By default none of your information is shared," he told InternetNews.com.

Fire Eagle gives users a granular control over the location information they share -- so one site might only be able to learn what country the person is in, while another might have access to his street address. Users always have the ability to "hide" or delete any information they no longer want available.

While the social networking applications spring to mind first, Coates sees the real benefit in providing more relevant local news and information. "When people hear this, they think that because it's about sharing your location, it's about sharing your location with people, and that's not the case." The mission of Fire Eagle, Coates said, is elegant in its simplicity: "Any site on the Web could with your permission respond to your location."

He imagines a search engine doing a more precise job of retrieving locally relevant results for a restaurant, for instance.

Asked whether Yahoo had plans to roll the feature out in its own search engine, Coates said that many of his colleagues had expressed interest in the project, but not to look for it "within the next few months."

Fire Eagle also extends to mobile Web sites, and seems a step closer to the long-deferred mobile advertising dream of being able to ping people with coupons as they walk in front of a business. So conceivably, people who opt-in to Fire Eagle could be opting in to geo-targeted ads.

"We think there are a number of ways that we think the Fire Eagle platform is good for Yahoo's business, and advertising is certainly one of them," Coates said.

He added that Fire Eagle's code of conduct for developers stipulates that they must be up-front and transparent when they explain to users how they will use the information, including what ad networks they might share it with.

"Rule No. 1 [is] don't be creepy," Coates said.

Yahoo launched Fire Eagle in a limited private beta in March. Coates said that Yahoo has been mulling the idea of a location-aware application for some time but that development began in earnest in the second half of last year.